/*
Copyright 2016 The Kubernetes Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package main

import (
	"net/http"
	"os"
	"path/filepath"
	"reflect"
	"testing"
)

const certsDir = "testdata"

func TestMakeKubeconfigHTTPClient(t *testing.T) {
	tests := []struct {
		kubeconfigPath string
		inClusterAuth  bool
		success        bool
	}{
		{
			kubeconfigPath: filepath.Join(certsDir, "kubeconfig"),
			inClusterAuth:  false,
			success:        true,
		},
		{
			kubeconfigPath: filepath.Join(certsDir, "kubeconfig"),
			inClusterAuth:  true,
			success:        false,
		},
		{
			kubeconfigPath: filepath.Join(certsDir, "kubeconfig-error"),
			inClusterAuth:  false,
			success:        false,
		},
		{
			kubeconfigPath: "",
			inClusterAuth:  false,
			success:        true,
		},
	}

	os.Setenv("KUBERNETES_SERVICE_HOST", "prometheus")
	os.Setenv("KUBERNETES_SERVICE_PORT", "8080")

	for _, test := range tests {
		t.Logf("Running test for: inClusterAuth %v, kubeconfigPath %v", test.inClusterAuth, test.kubeconfigPath)
		kubeconfigHTTPClient, err := makeKubeconfigHTTPClient(test.inClusterAuth, test.kubeconfigPath)
		if test.success {
			if err != nil {
				t.Errorf("Error is %v, expected nil", err)
				continue
			}
			if kubeconfigHTTPClient.Transport == nil {
				if test.inClusterAuth || test.kubeconfigPath != "" {
					t.Error("HTTP client Transport is nil, expected http.RoundTripper")
				}
			}
		} else if err == nil {
			t.Errorf("Error is nil, expected %v", err)
		}
	}
}

func TestMakePrometheusCAClient(t *testing.T) {
	tests := []struct {
		caFilePath      string
		tlsCertFilePath string
		tlsKeyFilePath  string
		success         bool
		tlsUsed         bool
	}{
		{
			caFilePath:      filepath.Join(certsDir, "ca.pem"),
			tlsCertFilePath: filepath.Join(certsDir, "tlscert.crt"),
			tlsKeyFilePath:  filepath.Join(certsDir, "tlskey.key"),
			success:         true,
			tlsUsed:         true,
		},
		{
			caFilePath:      filepath.Join(certsDir, "ca-error.pem"),
			tlsCertFilePath: filepath.Join(certsDir, "tlscert.crt"),
			tlsKeyFilePath:  filepath.Join(certsDir, "tlskey.key"),
			success:         false,
			tlsUsed:         true,
		},
		{
			caFilePath:      filepath.Join(certsDir, "ca.pem"),
			tlsCertFilePath: filepath.Join(certsDir, "tlscert-error.crt"),
			tlsKeyFilePath:  filepath.Join(certsDir, "tlskey.key"),
			success:         false,
			tlsUsed:         true,
		},
		{
			caFilePath:      filepath.Join(certsDir, "ca.pem"),
			tlsCertFilePath: "",
			tlsKeyFilePath:  "",
			success:         true,
			tlsUsed:         false,
		},
	}

	for _, test := range tests {
		t.Logf("Running test for: caFilePath %v, tlsCertFilePath %v, tlsKeyFilePath %v", test.caFilePath, test.tlsCertFilePath, test.tlsKeyFilePath)
		prometheusCAClient, err := makePrometheusCAClient(test.caFilePath, test.tlsCertFilePath, test.tlsKeyFilePath)
		if test.success {
			if err != nil {
				t.Errorf("Error is %v, expected nil", err)
				continue
			}
			if prometheusCAClient.Transport.(*http.Transport).TLSClientConfig.RootCAs == nil {
				t.Error("RootCAs is nil, expected *x509.CertPool")
				continue
			}
			if test.tlsUsed {
				if prometheusCAClient.Transport.(*http.Transport).TLSClientConfig.Certificates == nil {
					t.Error("TLS certificates is nil, expected []tls.Certificate")
					continue
				}
			} else {
				if prometheusCAClient.Transport.(*http.Transport).TLSClientConfig.Certificates != nil {
					t.Errorf("TLS certificates is %+v, expected nil", prometheusCAClient.Transport.(*http.Transport).TLSClientConfig.Certificates)
				}
			}
		} else if err == nil {
			t.Errorf("Error is nil, expected %v", err)
		}
	}
}

func TestParseHeaderArgs(t *testing.T) {
	tests := []struct {
		args    []string
		headers http.Header
	}{
		{
			headers: http.Header{},
		},
		{
			args: []string{"foo=bar"},
			headers: http.Header{
				"Foo": []string{"bar"},
			},
		},
		{
			args: []string{"foo"},
			headers: http.Header{
				"Foo": []string{""},
			},
		},
		{
			args: []string{"foo=bar", "foo=baz", "bux=baz=23"},
			headers: http.Header{
				"Foo": []string{"bar", "baz"},
				"Bux": []string{"baz=23"},
			},
		},
	}

	for _, test := range tests {
		got := parseHeaderArgs(test.args)
		if !reflect.DeepEqual(got, test.headers) {
			t.Errorf("Expected %#v but got %#v", test.headers, got)
		}
	}
}

func TestFlags(t *testing.T) {
	cmd := &PrometheusAdapter{
		PrometheusURL: "https://localhost",
	}
	cmd.addFlags()

	flags := cmd.FlagSet
	if flags == nil {
		t.Fatalf("FlagSet should not be nil")
	}

	expectedFlags := []struct {
		flag         string
		defaultValue string
	}{
		{flag: "v", defaultValue: "0"},                              // logging flag (klog)
		{flag: "prometheus-url", defaultValue: "https://localhost"}, // default is set in cmd
	}

	for _, e := range expectedFlags {
		flag := flags.Lookup(e.flag)
		if flag == nil {
			t.Errorf("Flag %q expected to be present, was absent", e.flag)
			continue
		}
		if flag.DefValue != e.defaultValue {
			t.Errorf("Expected default value %q for flag %q, got %q", e.defaultValue, e.flag, flag.DefValue)
		}
	}
}
